Add filter parameter support

$filter is a parameter documented in the Redfish specification, section
7.3.4.  It defines a mechanism for filtering arbitrary collections of
parameters based on a set of arbitrary language expressions.

From the specification, it supports the following language operators:

() Precedence grouping operator.
(Status/State eq 'Enabled' and Status/Health eq 'OK')
or SystemType eq 'Physical'

and Logical and operator.
ProcessorSummary/Count eq 2 and MemorySummary/TotalSystemMemoryGiB gt 64

eq Equal comparison operator.
ProcessorSummary/Count eq 2

ge Greater than or equal to comparison operator.
ProcessorSummary/Count ge 2

gt Great than comparison operator.
ProcessorSummary/Count gt 2

le Less than or equal to comparison operator
 MemorySummary/TotalSystemMemoryGiB le 64

lt Less than comparison operator.
MemorySummary/TotalSystemMemoryGiB lt 64

ne Not equal comparison operator.
SystemType ne 'Physical'

not Logical negation operator.
not (ProcessorSummary/Count eq 2)

or Logical or operator.
ProcessorSummary/Count eq 2 or ProcessorSummary/Count eq 4

Support for these operators have been added in previous commits.  This
commit enables them behind the insecure-enable-redfish-query meson
option.  This is an arbitrary language, so the likelihood there's some
improper implementation in the patch is high.  This gives folks the
ability to test it.

Tested:
Lots of unit tests included in this patch.

Functionally tested the basic operators:
```
GET /redfish/v1/Managers/bmc/LogServices/Journal/Entries?\$filter=EntryType+eq+'Oem'
GET /redfish/v1/Managers/bmc/LogServices/Journal/Entries?\$filter=EntryType+ne+'Oem'
```

Function as expected, producing multiple results or no results
respectively.

GET /redfish/v1 reports "FilterQuery": true

Redfish service validator passes.

Change-Id: Id568acc5dcfce868af12da5ee16c4f0caae8060a
Signed-off-by: Ed Tanous <ed@tanous.net>
diff --git a/redfish-core/lib/service_root.hpp b/redfish-core/lib/service_root.hpp
index fcaee98..57b967c 100644
--- a/redfish-core/lib/service_root.hpp
+++ b/redfish-core/lib/service_root.hpp
@@ -109,7 +109,7 @@
         BMCWEB_INSECURE_ENABLE_REDFISH_QUERY;
     protocolFeatures["ExpandQuery"]["NoLinks"] =
         BMCWEB_INSECURE_ENABLE_REDFISH_QUERY;
-    protocolFeatures["FilterQuery"] = false;
+    protocolFeatures["FilterQuery"] = BMCWEB_INSECURE_ENABLE_REDFISH_QUERY;
     protocolFeatures["OnlyMemberQuery"] = true;
     protocolFeatures["SelectQuery"] = true;
     protocolFeatures["DeepOperations"]["DeepPOST"] = false;